Charles Krauthammer caused grave unhappiness among some of his admirers last month when, speaking on Fox News, he attacked the Dutch politician Geert Wilders. At issue was Wilders’s campaign against the “Islamization” of Europe, particularly in the Netherlands. “What he says,” Dr. Krauthammer charged, “is extreme, radical, and wrong”:

He basically is arguing that Islam is the same as Islamism. Islamism is an ideology of a small minority which holds that the essence of Islam is jihad, conquest, forcing people into accepting a certain very narrow interpretation [of Islam].

The untruth of that is obvious. If you look at the United States, the overwhelming majority of Muslims in the U.S. are not Islamists. So, it’s simply incorrect. Now, in Europe, there is probably a slightly larger minority but, nonetheless, the overwhelming majority are not.

Dr. Krauthammer’s was not the only voice on Fox News condemning Wilders last month. Glenn Beck hauled out the “F-word,” describing Wilders as “fascist,” while William Kristol, the editor of The Weekly Standard, warned that Wilders was a “demagogue.”

So: Geert Wilders is a fascist demagogue who is extreme, radical, and (what’s more) wrong. Strong words. Are they justified?

A little background. As we write, Wilders, the founder and head of the Dutch Party for Freedom, is being prosecuted by the Dutch government for “hate speech,” “discrimination,” and similar outrages against political correctness. (He has also been indicted by Jordan for “inciting hatred.”) If he loses in Holland, he could face a two-year jail sentence. In the meantime, he lives with round-the-clock security in the face of numerous death threats. This is, remember, the country where the filmmaker Theo van Gogh was brutally murdered by jihadists in broad daylight.

What is the exact nature of Wilders’s tort? Well, in 2008 he wrote and sponsored a short film called Fitna, which juxtaposes verses from the Koran with contemporary images of violence perpetrated in the name of Islam. In its opening minutes, for example, the film flashes the text of Sura 8, Verse 60: “Prepare for them [i.e., for us] whatever force and cavalry ye are capable of gathering to strike terror into the hearts of the enemies.” The cavalry in question was United Airlines Flight 175, which is shown plowing into the South Tower of the World Trade Center as crowds of terrified people scramble to escape the carnage. Other verses are accompanied by images of Islamic violence against Jews, women, and apostates from Islam (“seize them and kill them wherever ye may find them,” Sura 4, Verse 89).

Wilders has also been vocal in his opposition to Islamic immigration and the institutionalization of Islamic law (Sharia) in the Netherlands. At the same time, he has campaigned vigorously for free speech, especially the freedom to criticize ideologies whose spread would stifle freedom. The New York Times sniffed that Wilders’s demand for free speech was a “bit rich” since he has also called for restrictions on the circulation of the Koran. A contradiction? Not necessarily. In the first place, defending free speech includes guarding against those who would deploy free speech only in order to abolish it. (“There is,” said Chesterton, “a thought that stops thought. That is the only thought that ought to be stopped.”) Secondly, as Wilders has explained, his call to restrict the circulation of the Koran mirrors the official Dutch restrictions on Mein Kampf, the sale of which is illegal in Holland. The whole idea of “banning” books is anathema to most Americans. But Wilders’s point is that if Hitler’s incitement to hatred is restricted in Holland (as it is in some other parts of Europe), why not the Koran?

Two points about Dr. Krauthammer’s charge that Wilders fails to distinguish between “Islam” (the faith of 1.4 billion to which we are not supposed to object) and “Islamism” (the bad or perverted form of Islam to which only “a minority” subscribes). First, it is worth stressing that Wilders has repeatedly acknowledged that most Muslims are peaceful. Speaking in London recently, for example, he noted that

The majority of Muslims are law-abiding citizens and want to live a peaceful life as you and I do. I know that. That is why I always make a clear distinction between the people, the Muslims, and the ideology, between Islam and Muslims. There are many moderate Muslims, but there is no such thing as a moderate Islam.

Is Wilders right? If so (and this is our second point), then we have to question whether Dr. Krauthammer’s contrast between “Islam” and “Islamism” is the relevant distinction. Andrew C. McCarthy got to the nub of the issue last month in a column for National Review Online. “Personally,” Mr. McCarthy wrote, “I don’t think there is much difference, if any, between Islam and Islamism.”

Islamists are Muslims who would like to see sharia (Islamic law) installed. That is the necessary precondition to Islamicizing a society. It is the purpose of jihad. The terrorists are willing to force sharia’s installation by violent jihad; other Islamists have varying views about the usefulness of violence, but they also want sharia, and their jihadist methods include tactics other than violence. I reluctantly use the term “Islamist” rather than “Islam” because I believe there are hundreds of millions of Muslims … who do not want to live under sharia, and who want religion to be a private matter, separated from public life. It is baffling to me why these people are Muslims since, as I understand Islam, (a) sharia is a basic element, and (b) Islam rejects the separation of mosque and state. But I’m not a Muslim, so that is not for me to say. I think we have to encourage the non-sharia Muslims and give them space to try to reform their religion, so I believe it’s worth labeling the sharia seekers “Islamists” in order to sort them out. But I admit being very conflicted about it because I also concede that the Islamists have the more coherent (and scary) construction of Islam. We wouldn’t be encouraging reform if we really thought Islam was fine as is.

Wilders does not need to be lectured condescendingly about distinctions within Islam, because he lives with them every day. And he has concluded, notwithstanding Dr. Krauthammer’s views on the precise “minority” that identifies as “Islamist,” that Islam itself is the issue—and that, therefore, regardless of the “moderation” of the “overwhelming majority” of Muslims, the more Islam the less Netherlands in any recognizable sense.

The point is that “Islamism” is a term that has been seized upon by anxious Westerners eager to cordon off the toxic appendage of Islamic ideology from the (we are assured) benign host. Both the anxiety and the eagerness are understandable. We saw them in operation in the immediate aftermath of 9/11 when President Bush stood astride the smoldering ruins of the World Trade Center and told the world that “Islam” meant “peace” (really, it means “submission” as in “submission to the will of Allah,” but perhaps it would have been impolitic to point that out). At that time, policy makers had yet to settle on “Islamism” as a preferred linguistic repository for this political feint, but the President was appealing to the same vertiginous compact of nervousness, fear, good will, and hope...